FBMC is a multi-carrier modulation technology. Compared with orthogonal frequency division multiplexing (OFDM), the FBMC has lower out-of-band radiation and higher spectrum efficiency, and has promising prospects of application. An important characteristic of the FBMC is that mutual interference, to different extents, exists between adjacent subcarriers and between adjacent FBMC symbols. For example, a transmitted symbol on any time-frequency resource generates an additional received signal at a position of an adjacent time-frequency resource, thereby causing interference to a wanted received signal.
A typical FBMC implementation solution is using an OFDM/offset quadrature amplitude modulation (OQAM) technology. A difference of OFDM/OQAM from the OFDM lies in that pure-real-number or pure-imaginary-number OQAM symbols are transmitted in an OFDM/OQAM system, and are mapped onto time-frequency resource elements by using a law of real-imaginary alternation. However, interference caused by a transmitted symbol to a received signal always occurs on an imaginary part or real part that is corresponding to the transmitted symbol. Therefore, if a channel can keep unchanged in time-domain and frequency-domain ranges, the interference can be canceled by performing an operation of separating the real part from the imaginary part after channel equalization is performed.
However, in an actual application, generally, the channel cannot be unchanged in the time-domain and frequency-domain ranges. If the channel changes significantly in a time-domain or frequency-domain dimension, mutual interference is still generated between transmitted symbols in a time-domain border or frequency-domain border in which the channel changes. In a broadband multi-carrier system, a change of a channel in a frequency domain is relatively sharp, and the broadband multi-carrier system widely uses a frequency division multiple access technology, which also leads to a significant change of the channel in the frequency domain. Therefore, how to cancel mutual interference in the frequency-domain border is still pending.